<?php

// +----------------------------------------------------------------------

// | ThinkPHP [ WE CAN DO IT JUST THINK IT ]

// +----------------------------------------------------------------------

// | Copyright (c) 2006-2013 http://thinkphp.cn All rights reserved.

// +----------------------------------------------------------------------

// | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 )

// +----------------------------------------------------------------------

// | Author: liu21st <liu21st@gmail.com>

// +----------------------------------------------------------------------

namespace Think\Cache\Driver;

use Think\Cache;

defined('THINK_PATH') or exit();



/**

 * Redis缓存驱动 

 * 要求安装phpredis扩展：https://github.com/nicolasff/phpredis

 */

class Redis extends Cache {

	 /**

	 * 架构函数

     * @param array $options 缓存参数

     * @access public

     */

    public function __construct($options=array()) {

        if ( !extension_loaded('redis') ) {

            E(L('_NOT_SUPPERT_').':redis');

        }

        if(empty($options)) {

            $options = array (

                'host'          => C('REDIS_HOST') ? C('REDIS_HOST') : '127.0.0.1',

                'port'          => C('REDIS_PORT') ? C('REDIS_PORT') : 6379,

                'timeout'       => C('DATA_CACHE_TIMEOUT') ? C('DATA_CACHE_TIMEOUT') : false,

                'persistent'    => false,

            );

        }

        $this->options =  $options;

        $this->options['expire'] =  isset($options['expire'])?  $options['expire']  :   C('DATA_CACHE_TIME');

        $this->options['prefix'] =  isset($options['prefix'])?  $options['prefix']  :   C('DATA_CACHE_PREFIX');        

        $this->options['length'] =  isset($options['length'])?  $options['length']  :   0;        

        $func = $options['persistent'] ? 'pconnect' : 'connect';

        $this->handler  = new \Redis;

        $options['timeout'] === false ?

            $this->handler->$func($options['host'], $options['port']) :

            $this->handler->$func($options['host'], $options['port'], $options['timeout']);

    }



    /**

     * 读取缓存

     * @access public

     * @param string $name 缓存变量名

     * @return mixed

     */

    public function get($name) {

        N('cache_read',1);

        $value = $this->handler->get($this->options['prefix'].$name);

        $jsonData  = json_decode( $value, true );

        return ($jsonData === NULL) ? $value : $jsonData;	//检测是否为JSON数据 true 返回JSON解析数组, false返回源数据

    }



    /**

     * 写入缓存

     * @access public

     * @param string $name 缓存变量名

     * @param mixed $value  存储数据

     * @param integer $expire  有效时间（秒）

     * @return boolean

     */

    public function set($name, $value, $expire = null) {

        N('cache_write',1);

        if(is_null($expire)) {

            $expire  =  $this->options['expire'];

        }

        $name   =   $this->options['prefix'].$name;

        //对数组/对象数据进行缓存处理，保证数据完整性

        $value  =  (is_object($value) || is_array($value)) ? json_encode($value) : $value;

        if(is_int($expire)) {

            $result = $this->handler->setex($name, $expire, $value);

        }else{

            $result = $this->handler->set($name, $value);

        }

        if($result && $this->options['length']>0) {

            // 记录缓存队列

            $this->queue($name);

        }

        return $result;

    }



    /**

     * 删除缓存

     * @access public

     * @param string $name 缓存变量名

     * @return boolean

     */

    public function rm($name) {

        return $this->handler->delete($this->options['prefix'].$name);

    }



    /**

     * 清除缓存

     * @access public

     * @return boolean

     */

    public function clear() {

        return $this->handler->flushDB();

    }



}

